1 files changed, 22 insertions, 3 deletions
diff --git a/clang/lib/Sema/SemaDeclObjC.cpp b/clang/lib/Sema/SemaDeclObjC.cpp
index ac1e3923afa..f28abf4c070 100644
--- a/clang/lib/Sema/SemaDeclObjC.cpp
+++ b/clang/lib/Sema/SemaDeclObjC.cpp
@@ -600,7 +600,8 @@ ActOnSuperClassOfClassInterface(Scope *S,
   }
 }
 
-DeclResult Sema::actOnObjCTypeParam(Scope *S, IdentifierInfo *paramName,
+DeclResult Sema::actOnObjCTypeParam(Scope *S, unsigned index,
+                                    IdentifierInfo *paramName,
                                     SourceLocation paramLoc,
                                     SourceLocation colonLoc,
                                     ParsedType parsedTypeBound) {
@@ -643,6 +644,23 @@ DeclResult Sema::actOnObjCTypeParam(Scope *S, IdentifierInfo *paramName,
       // Forget the bound; we'll default to id later.
       typeBoundInfo = nullptr;
     }
+
+    // Type bounds cannot have explicit nullability.
+    if (typeBoundInfo) {
+      // Type arguments cannot explicitly specify nullability.
+      if (auto nullability = AttributedType::stripOuterNullability(typeBound)) {
+        // Look at the type location information to find the nullability
+        // specifier so we can zap it.
+        SourceLocation nullabilityLoc
+          = typeBoundInfo->getTypeLoc().findNullabilityLoc();
+        SourceLocation diagLoc
+          = nullabilityLoc.isValid()? nullabilityLoc
+                                    : typeBoundInfo->getTypeLoc().getLocStart();
+        Diag(diagLoc, diag::err_type_param_bound_explicit_nullability)
+          << paramName << typeBoundInfo->getType()
+          << FixItHint::CreateRemoval(nullabilityLoc);
+      }
+    }
   }
 
   // If there was no explicit type bound (or we removed it due to an error),
@@ -653,8 +671,8 @@ DeclResult Sema::actOnObjCTypeParam(Scope *S, IdentifierInfo *paramName,
   }
 
   // Create the type parameter.
-  return ObjCTypeParamDecl::Create(Context, CurContext, paramLoc, paramName,
-                                   colonLoc, typeBoundInfo);
+  return ObjCTypeParamDecl::Create(Context, CurContext, index, paramLoc, 
+                                   paramName, colonLoc, typeBoundInfo);
 }
 
 ObjCTypeParamList *Sema::actOnObjCTypeParamList(Scope *S,
@@ -868,6 +886,7 @@ ActOnStartClassInterface(Scope *S, SourceLocation AtInterfaceLoc,
             ObjCTypeParamDecl::Create(
               Context,
               CurContext,
+              typeParam->getIndex(),
               SourceLocation(),
               typeParam->getIdentifier(),
               SourceLocation(),